Julia, I agree that an unsolicited recommendation regarding my love life would be inappropriate. And I would be as vocal as you about it.
With that said, there has been a lot of attention paid to sexual dysfunction in women lately. It wouldn't surprise me at all if the patient were the one to broach the subject and wasn't happy with the suggestion that her weight, not hormone levels, may be the reason she's experiencing problems. Of course, we don't know exactly what was said or in what tone so I am just speculating. Still I would expect there to be more than just one complaining patient if he were that offensive a doctor.
Personally, I prefer a doctor that doesn't beat around the bush when it comes to my health. But, then again, I am really, really hard to offend!